Flexible diaphragm assemblage



Jan. 16, 1945. c. .1. SEKERA 2,367,624

FLEXIBLE DIAPHRAGM ASSEMBLAGE Filed Sept. 14, 1943 41E Ii 16 M- 15 INVENTOR CHAR LE 5 J. EEKERA BY a Z ATTORNEY Patented Jan. 16, 1945 FLEXIBLE DIAPHRAGM ASSEMBLAGE Charles J. Sekera, Turtle Creek, Pa., assignor to The Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Application September 14, 1943, Serial No. 502,279

6 Claims.

This invention relates to flexible diaphragm assemblages and more particularly to diaphragm assemblages of the type arranged to actuate a valve.

Extensive use is made of flexible diaphragm assemblages in the fluid pressure brake art, for example in the regulating portion 2 of feed valve devices of the type shown, described and claimed in the patent to Farmer, No. 1,784,227 issued April 15, 1930. Briefly stated, such a diaphragm assemblage comprises a flexible diaphragm subject on one side to the pressure of a coil spring which acts through the medium of a spring seat and a diaphragm follower and subject on the opposite side to fluid under pressure and is employed to control the operation of a fluid supply valve.

While such assemblages have enjoyed extensive use and entirely meet the requirements of certain classes of service, they have in certain other and more severe classes of service a tendency to produce a binding or cocking action between the spring seat and the diaphragm follower and the closely associated follower ring, with the result that undesired action of the assemblage is effected.

The principal object of the invention is to provide an improved flexible diaphragm assemblage with centering or guiding means for eliminating any binding or cooking action between the spring seat and the diaphragm follower and follower ring,

In the accompanying drawing Fig. 1 is a central vertical section of a feed valve regulating portion embodying the invention; Fig. 2 is. a fragmentary view of a feed valve regulating portion embodying another form of the invention.

For the purpose of illustration the centering or guiding means will be described in connection with the diaphragm assemblage forming a part of the regulating portion of a feed valve device, but it will be understood that this is merely illustrative and that the centering or guiding means may be used in any similar diaphragm assemblage no matter where such assemblage may be employed.

As shown in Fig. 1 of the drawing, the regulating portion of a feed valve device embodying the invention may comprise a casing I containing a flexible diaphragm 2. This diaphragm is clamped against a shoulder 3, provided on the casing I,

by means of a diaphragm follower ring 4 which is provided with a downwardly extending recess 40. which is open at its upper end, the ring 4 being clamped in place by a combined spring box and nut 5 which is threaded at 6 into a circular opening formed in the lower face of the casing.

Engaging the lower face of the diaphragm 2 is a diaphragm follower 1 which moves freely in the recess 40. of the diaphragm follower ring 4. The bottom of this recess is provided with a central opening db. The follower l is provided with a centrally located downwardly depending stem 8 which passes through a suitable aligned aperture in a centering disc I0 movably mounted in the recess 4a, clearance between the walls of the aperture and the stem being held to a minimum to insure a close flt. The lower face of the follower 7 engages the upper face of the disc l0 and the stem 8 of the follower projects into a central opening ll provided in a spring seat l2, which opening is in alignment with the aperture in the disc it. This spring seat extends through the opening 4b in the follower ring 4 and its upper face operatively engages the lower face of the disc ID.

The outside diameter of the centering disc 10 is of such size that it slidably fits in the recess 6a of the follower ring 4 and as a result will positively center the diaphragm follower l and thereby the spring seat 12 upon the diaphragm 2. With the diaphragm follower and the spring seat thus positively guided for motion in a definite plane parallel with the normal plane of the diaphragm, the assemblage will be free of any cocking or binding action between the spring seat, diaphragm follower, follower stem and follower ring.

Threaded into the lower end of the spring box 5 is an adjustable spring seat M which may be turned by a hand wheel l5 and which supports the lower end of a coil spring I6. The upper end of the coil spring 16 engages the lower face of the spring seat l2. 1

At the upper face of the diaphragm 2 there is a chamber l8 which is in constant open communication with a fluid conducting passage l9 pro vided in the casing I.

The casing I is also provided with a chamber 20 which is in constant open communication with a fluid conducting passage 2|. Contained in chamber 20 is a valve 22 having a fluted stem 23 slidably mounted in a bushing 24 provided in a bore through a wall 25 separating chambers l8 and 20. The valve 22 and stem 23 are arranged in coaxial relation with the diaphragm 2 and the end of said stem, in the present embodiment of the invention,

engages the diaphragm. A spring 26 in chamber 2!) acts on valve 22 for urging same into sealing 2t engagement with a valve seat provided on the adjacent end of the bushing.

In normal operation, when fluid pressure supplied through passage I9 to chamber 18, exceeds the regulating spring pressure exerted on the opposite side of the diaphragm, the diaphragm is deflected downwardly permitting the spring 26 to maintain the valve 22 seatedwhen fluid pressure supplied through passage I9 to chamber I8 is reduced below the opposing pressure of spring [6, the diaphragm will deflect upwardly to unseat the valve 22 and establish communication between chambers l8 and 20.

The embodiment of the inventionrshown-infig. 2 of the drawing is similar to that shownin Rig. 1

except that the centering disc is. made to flex.

and the outside diameter thereof is arranged to fit closely into a radial groovefldprovided in the diaphragm follower ring 4, there being a sliding fit between the diaphragm and the side walls of the groove to accommodate the flexing of the diaphragm. It should here be mentioned that the movement of the peripheral edge of the disc from the bottom of the groove when the disc flexes will beless than-the usual clearance space between the spring seat [2 and the followerring 4, thus insuring against cooking or binding action between the associated parts.

From the foregoing description it will beunderstood that when a centering disc I such asillustrated in eitherFig. 1: or Fig; 2 of the drawing is employed thediaphragm follower 1 will be guided against lateral'canting or binding: action and will move freely in: the central opening through the follower. ring 4', thusinsuring against friction, of the parts. It will, also-.be understood that the construction: is simple, inexpensive to manufacture and easy. to assemble and. disassemble.

Having now described my invention, what I claim as new and desire to secure by LettersPatcut, is:

1. In a diaphragm assemblage comprising; in combination, a; flexible: diaphragm, a; diaphragm follower ring for clamping said diaphragm in place, a diaphragm follower engaging said diaphragm and provided; with astem, a spring-seat provided with an aperture tov receive said stem". and centering means interposed between; said ,f 01:- lower and said springseat and cooperatingwith said follower to insure-against lateral; motion of said spring seat relative to said diaphragm; fol,- lower and follower ring.

2. In a diaphragm. assemblage comprising in combination, a flexible diaphragm, a diaphragm, follower ring for clamping said diaphragm in place, a diaphragm follower engaging, said diaphragm and provided-with a stenma spring seat.

provided with an aperture to receive said stem, and centering means interposedibetween said-follower and said spring seat and cooperating with said follower to insure against lateral motion of said spring seat relative to said diaphragm fol- .lower and follower ring, said centering means comprising a thin disc having a central centering aperture through which said stem passes.

3. In a diaphragm assemblage comprising in combination.v a, flexible. diaphragm, a diaphragm follower ring, for clamping said diaphragm in place, a diaphragm follower engaging said diaphragm and provided with a stem, a spring seat provided with an aperture to receive said stem, and a centering'disc interposed between said follower andsaid spring seat and having an outside diameter. cooperating with said follower ring to insure againstlateral motion of said spring seat relative to said diaphragm follower and follower ring;

4. In a diaphragm assemblage comprising in combination, a flexible diaphragm, a diaphragm followerring. for: clamping said diaphragm in place; adiaphragm. follower engaging said dia-.

phragm andprovided with a stem, a spring-seat provided with an aperture to receive said stem, and a centering disc interposed betweensaidiollower and said spring; seat and having a central centering aperture through which said stem passes andan outside diameter cooperatingwith saidfollower ring toinsure against lateral motion of saidspring seatrelative to said diaphragmv fol.- lower andfollower ring.

5, In a diaphragm assemblage comprising in combination, a flexible diaphragm follower ring for, clamping said. diaphragm in, place, said. diaphragm follower ring having an annular recess.

a diaphragm. follower engaging said diaphragm and providedwith a stem,,a spring seat provided with an aperture to receive said stem, and a centering disc interposed between and operatively engaged by said follower and spring seat, said centering disc having an outside diameter extending into said recessand cooperating with said follower to insure against lateral motion of. said spring seat relative to. said diaphragm follower and-follower ring;

6. In a diaphragm assemblage comprising in combination, a; flexible diaphragm, a diaphragm follower ring for clamping: saiddiaphragm in place, said diaphragm follower ring having an annular recess, a diaphragm follower engagingsaid' diaphragm and provided with a stem, a

spring seat provided with an aperture to receive said stem, and a centering disc-cooperating with said diaphragm follower ring toinsure against lateral motion ofsaid spring seat relative t'o-said diaphragm follower and follower ring, saidcentering' disc having a central aperture through which saidstem passes-and an-outer edgeportion which projects intosaidrecess.

CHARLES J. SE'KERA; 

